Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 4 ones in any 3 X 3 X 3 subtriangle.

A153929

Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 4 ones in any 3 X 3 X 3 subtriangle.

Terms

    a(0) =1a(1) =2a(2) =2a(3) =3a(4) =13a(5) =21a(6) =81a(7) =653a(8) =2032a(9) =13521a(10) =198411a(11) =1134105a(12) =14051578a(13) =384943878a(14) =4075092077a(15) =94920910164

External references